A novel method for identifying damage in transverse joints of arch dams from seismic responses based on the feature of local dynamic continuity interruption

Abstract

Without the difficulty of applying particular excitations on arch dams, a method using the correlation coefficients of time-scale representations (CCTSRs) of seismic responses to identify the damage in transverse joints is proposed. The identification of damage using the CCTSR method is characterized by comparing the time-scale representations (TSRs) of paired seismic accelerations measured from two neighbouring points crossing the transverse joints horizontally. With the CCTSR method, the TSRs of measured seismic accelerations are produced with the continuous wavelet transform; the comparison of the TSRs is carried out by calculating the correlation coefficients. The correlation coefficients of the paired TSRs are combined with the defined damage intervals to evaluate the positions and severities of the damage. The method’s feasibility is numerically verified via the identification of the damage in transverse joints by discussing the effects of the wavelet functions, seismic excitations, and noise resistance. The method’s effectiveness is experimentally validated via the detection of the damage in transverse joints of a scaled arch dam model subjected to artificial seismic loads. The proposed CCTSR method can localize the positions of various damage scenarios and quantify the damage severities caused by progressive seismic loads.

Modal Parameter Recursive Estimation of Concrete Arch Dams under Seismic Loading Using an Adaptive Recursive Subspace Method

“…During the normal operation of a concrete arch dam, the inherent modal parameters of the structure do not change with time and can be identified using the aforementioned time-invariant structural modal parameter identification methods. However, in another scenario, as an arch dam experiences damage from seismic loading, and with the gradual accumulation and progression of damage, the modal parameters of the arch dam change over time [ 11 , 28 ]. In such cases, a time-varying modal parameter (TMP) identification method needs to be employed.…”